1. Technical Field
The present invention is directed generally to a quick disconnect coupling and more particularly to such a coupling wherein both the male and female coupling members include valves for automatic closure upon uncoupling and gas pressure differential venting is provided for between the atmosphere and the container onto which the coupling is mounted.
2. Description of the Prior Art
Quick disconnect couplings for liquid flow conduits such as pipes and hoses are known and commercially available. Examples include the quick disconnect couplings of U.S. Pat. Nos. 4,436,125 and 5,316,041 of Colder Products Company. One or more of the following problems are associated with all of the known quick disconnect couplings, thereby limiting their effectiveness.
First, many of the couplings include O-ring seals which tend to wear and leak in response to repeated coupling and uncoupling cycles or in response to the action of liquid chemicals to which they may be exposed. The inconvenience and expense of monitoring the age and condition of such O-ring seals places an impractical burden on users and creates an exposure to risk of leakage from unmonitored couplings. Such O-rings generally require an interruption between the engaged surfaces of the coupling members, thereby reducing the stability of the coupling and increasing the chances for leakage.
Secondly, a failure to provide an automatically actuated valved closure on both halves of the coupling member creates risk of leakage, upon disconnection of the coupling halves, from either of the fluid conduits or containers to which the coupling halves are connected.
Thirdly, a substantial space between the closure valves in the coupling halves creates the risk of spillage of any liquid situated between the valves upon disconnection of the coupling halves.
Finally, a lack of atmospheric venting through at least one of the coupling halves limits their effectiveness for use on fluid containers in which positive or negative pressure differentials are created either by the fluids themselves or by the action of filling the container or dispensing fluid therefrom. Lack of adequate venting causes safety and quality concerns because negative pressure within a fluid container interferes with dispensing of the fluids by the metering guns which are in common use. Likewise, negative pressure may cause collapsing of a bottle which can result in a toppling over. It is also important that any venting system be spaced sufficiently from the liquid flow into and from a container that the venting gases are not drawn into the liquid stream.
Accordingly, a primary object of the invention is to provide an improved quick disconnect coupling.
Another object is to provide an effective vented quick disconnect coupling.
Another object is to provide a quick disconnect coupling with valves on both coupling members which are automatically closed upon uncoupling.
Another object is to provide a quick disconnect coupling having automatic closure valves situated closely adjacent the engaged ends of the coupling members to minimize and eliminate any free fluid between them upon uncoupling of the coupling members.
Another object is to provide a quick disconnect coupling which minimizes or eliminates O-ring seals.
Another object is to provide a quick disconnect coupling adapted for use on any liquid container including, but not limited to, pails, jars, vials and bottles.
Another object is to provide a quick disconnect coupling in which the seals are not subject to chemical erosion.
Another object is to provide a quick disconnect coupling which maximizes surface engagement between the coupling members for maximum stability and elimination of leakage.
Another object is to provide a quick disconnect coupling which affords a visual indication of whether the coupling members are locked together.
Another object is to provide a quick disconnect coupling with effective venting for accurate dispensing of liquid from a container on which the coupling is mounted.
Another object is to provide a quick disconnect coupling with effective venting which enables usage on thinner walled and less expensive containers.
Finally, an object is to provide a quick disconnect coupling which is simple and rugged in construction, economical to manufacture and efficient in operation.